Depth to the curie isotherm from aeromagnetic data and geothermal considerations for the western sector of the trans-Mexican volcanic belt

Abstract

Preliminary depth estimations to the Curie isotherm in the western sector of the Trans-Mexican Volcanic Belt (TMVB) are reported. Depth estimations are based on spectral analysis of aeromagnetic data along seven profIles. The Curie point isotherm lies between 7 and 18 km deep. Corresponding heat flow values derived from the analysis roughly delineate two high heat flow zones which are related to relatively young geologic structures, i.e. the Tepic graben and the Amealco caldera. A third zone of intermediate heat flow values coincides with the presence of colder and deeper hydrothermal systems in the neighborhood of Puruándiro. The Curie point Depth estimates correlate with the pattern of heat flow measurements and of equilibrium temperatures characteristic of TMVB hydrothermal systems. Preliminary estimations of the potential geothermal energy stored between the surface and the Curie point isotherm are also reported.